Apparatus and method for determining the internal cleanliness of a tube

ABSTRACT

A system to measure the internal state of a bundle of tubes by injecting a signal into each tube of the bundle, receiving reflections from the tube due to anomalies within the tube, then analyzing the reflections to determine the type or characteristics about the anomalies. The analyzed information is stored in database to be used for statistical processing. Further, the device can be used in the performance of a cleaning process by conducting an initial assessment of the tubes in a bundle of tubes, comparing the stored data and estimating the number of cleaning cycles that will be required, and re-conducting the evaluation of the state of the tubes after every cleaning cycle or after every few cleaning cycles.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a non-provisional application being filed under 35USC 111 and 37 CFR 1.53(b) as a continuation application of the UnitedStates application for patent that was filed on Aug. 16, 2013 andassigned Ser. No. 13/969,051, wherein Ser. No. 13/969,051 is acontinuation application of the United States application for patentthat was filed on Nov. 4, 2010 and assigned Ser. No. 12/939,455 andissued as U.S. Pat. No. 8,534,144 on Sep. 17, 2013, which patent claimsthe benefit under 35 USC 119(e) of the prior filing date of the UnitedStates Provisional Application for patent that was filed on Nov. 4, 2009and assigned Ser. No. 61/257,869, and was filed as acontinuation-in-part of the United States national patent applicationthat was filed on Jan. 23, 2008 and assigned Ser. No. 11/996,503, whichapplication claims priority to the PCT application PCT/IL06/000860 thatfiled on Jul. 25, 2006, and which further claims priority to the UnitedStates provisional application that was filed on Jul. 29, 2005 andassigned Ser. No. 60/703,450. Each of the above referenced UnitedStates, PCT and provisional applications are herein incorporated byreference in their entirety.

BACKGROUND

There is a variety of applications that utilize tubes, or a bundle oftubes for delivering or extracting liquid, gas, etc. A few non-limitingexamples of such applications are seen in systems such as typicalplumbing environments, large-scale plumbing environments, heatexchangers, reactors, boiler systems, etc. More particularly, one cantypically observe the use of heat exchangers in systems such as powerstations, refineries, chemical plants, air conditioning systems, etc. Inapplications that employ the use of such tubing for the transfer ofliquid, the fluid flowing through the tubes may result in thefacilitation of an accumulation of deposits on the inner surface of thetubes. The accumulation of such deposits results in degrading theefficiency of the tube and/or bundle of tubes. The accumulation in suchenvironments may depend on a variety of circumstances, such as theambient temperature of operation, the contents of the liquid, the flowrate, the flow volume, the type of material used in fabricating thetubes, the shape of the tubes (straight or bent), the size of the innerdiameter, etc. As such, the accumulation of deposits on the innersurface of the tube(s) can occur at a variety of rates ranging fromgradual to rapid accumulation. The accumulation of the deposits withinthe interior of the tube and/or tubes can have an adverse effect on theoperation of the system utilizing the tubes. For instance, theaccumulation may result in the reduction of heat transfer, reduction inthe ability to cool a system or simply an obstruction of flow.Therefore, it is common practice in the maintenance of such systems toclean out the tubes periodically. The cleaning process is complicated bythe fact that some deposits, for example scale, can be very hard toremove. To successfully clean and maintain the tubes, the cleaningprocess often involves several cleaning stages for the successiveremoval of such deposits.

Measuring the effectiveness of the cleaning process at the end of eachstage and/or at the conclusion of the process is a difficult task. Thereare a few known methods for evaluating the cleaning. The most commonmethod is to examine the tubes visually using a borescope. However,using a borescope in a bundle of tubes is very time consuming. Inaddition the borescope can only be used in the examination of straighttubes. Furthermore, the results of the evaluation using a borescope areobjective and depend greatly upon the capabilities, judgment, opinionsand the current condition of the user conducting the evaluation.

It should also be appreciated by those of ordinary skill in the art thatthe methods utilized in the current state of the art suffer from severaldeficiencies, such as but not limited to, the amount of time required inperforming the evaluation, the dependency on the operator, thelimitation of not being used in bundles of curved tubes, etc.

BRIEF SUMMARY

There is a need in the art for a technique and/or system and/or methodthat can measure or evaluate the cleanliness or clearness of a largenumber of tubes, such as a bundle of tubes, in a timely manner.Furthermore, there is a need in the art for a technique and/or systemand/or method that can perform an evaluation of tubes objectively andautomatically, independent of the capabilities and judgments of the useror operator. There is also a need for a technique and/or system and/ormethod that can evaluate the cleanliness or clearness of bent, curvedand spiraled tubes.

The above-described deficiencies do not limit the scope of the inventiveconcepts of the present disclosure in any manner. The deficiencies arepresented for illustration only.

Several exemplary embodiments of a measurement apparatus, that performsa quality control analysis of the remedial process, which may include acleaning process, purging process, resurfacing process, etc., aredescribed. An exemplary embodiment first applied before the remedialprocess commences in order to assess the initial condition of the tubes.It is then applied successively after each stage of cleaning to assessthe effectiveness of each act of the cleaning process, showing thepresent condition of the tubes and giving indications whether additionalcleaning phases are necessary.

More particularly, one embodiment of the measuring device or system thatcan be used in the above-described cleaning process is used to evaluatethe interior state of one or a plurality of tubes, such as in a bundleof tubes. The system includes a processing unit or some processingcapability or control capability (collectively referred to as aprocessing unit). The processing unit interfaces to a signal injectorand a signal detector. The signal detector includes an interface tube,which is an element that can be coupled or interfaced to a tube to betested. The signal injector operates to create a wave in the tube. Thewave can be an acoustic wave for example. In other embodiment the wavecan be electro-magnetic waves or other signal types. The wave thenpropagates into the target tube, the tube under test. As the waveencounters constrictions within the interior of the tube, such asdeposits, accumulations, fractures, pits, etc., the wave or portionsthereof is reflected. The reflected waves propagate back up the tubewhere a sensor, such as a pressure sensor, transducer, etc., detects asignal, which was created from the received reflected waves. Thedetected signal, or information about the reflected wave, is thenprovided to the processing unit, which can then evaluate the informationto identify what, if any, anomalies are present in the tube.

In conducting the evaluation, the processing unit operates to identifystatistical information concerning the anomalies in each target tubeincluding statistics such as the number of blockages, number of cleaningcycles required to restore tube interior to a desired status or athreshold state of cleanliness, the number of faults in the tube, thepercentage of blockage, etc.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING

FIG. 1 is a block diagram illustrating relevant elements of an exemplaryembodiment of a system for measuring and evaluating the cleanliness of aplurality of tubes.

FIG. 2 is a waveform timing diagram that illustrates typical reflectionsfrom a local blockage and a local degradation in a target tube.

FIG. 3 is a signal diagram illustrating overlaid traces of measurementsfrom several exemplary dirty target tubes.

FIG. 4 is a signal diagram illustrating overlaid traces of signalscorresponding to internal surface of the target tubes after cleaning.

FIG. 5 is a flow diagram illustrating relevant acts of an exemplarymethod for analyzing and evaluating the effectiveness of a cleaningprocess.

FIG. 6 is a functional block diagram of the components of an exemplaryembodiment of the measuring system, as well as other embodimentsthereof.

DETAILED DESCRIPTION OF EMBODIMENTS OF THE INVENTION

The disclosure describes various embodiments, as well as features,aspects functions, etc. of such embodiments of a tube testing device.Various embodiments of the tube testing device are based on the use ofAcoustic Pulse Reflectometry (APR).

Now turning to the figures, the various embodiments, as well asfeatures, aspects and functions that may be incorporated into thevarious embodiments are described in more detail.

FIG. 1 is a block diagram illustrating relevant elements of an exemplaryembodiment of a system for measuring and evaluating the cleanliness of aplurality of tubes. The illustrated hardware components of the exemplarymeasuring system are configured to provide Non Destructive Testing(NDT). It should be noted that the configuration illustrated in FIG. 1is used for illustration purposes only and therefore is not in shown toany particular scale and the illustrated functional boundaries are notabsolutely necessary in the actual implementation of the measuringsystem. For example, the length of the interface tube 112 can beshorter, longer or the same as the length of the exchanger tube 114.

The illustrated embodiment includes a signal injector 120 and a signaldetector 130. It should be understood that the term signal and wave isused interchangeably in this description and encompasses any form ofenergy that can be propagated through the tube and reflected anddetected. The signal injector 120 is configured to inject a signal intoa medium, or interface tube 112, which acts as an interface to thetarget tubes being tested 114. The signal detector 130 includes a sensorthat detects signal reflected back from the target tubes 114 into theinterface tube 112. The signal injector 120 and signal detector 130 mayoperate as a stand-alone unit, a stand-alone unit that interfaces and/orreports information to other system, a support unit that is controlledby an external processing unit 102, as well as other structures and/orconfigurations. For instance, in the stand-alone configuration, theprocessing unit may be incorporated into the signal injector and/or thesignal detector 130. In such embodiments, the processing unit 102 may beas simple as a microcontroller, an ASIC or even simply analog and/ordigital control circuitry. The stand-alone unit may include a userinterface for initiating a test sequence or, it may simply be activatedby coupling the interface tube 112 to a tube under test 114. Therecorded signal may be stored in internal memory and/or informationregarding the detection may be displayed to a user in a variety ofmanners including the use of an LCD or even simple codes displayed usinglights or numbers, or audible sounds such as error codes or certaintones or buzzers may also be used.

In the illustrated embodiment, the signal injector 120 is coupled to theprocessing unit 102 and the tube under test 114. The signal detector 130is coupled to the processing unit 102 and the tube under test 114.

More specifically, in the illustrated measuring system, the processingunit 102 synthesizes an acoustic pulse which is transmitted through atransmitter 110 via an amplifier 106. Thus, the processing unit 102 mayinclude a signal generator or, a signal generator can be external to theprocessing unit 102, such as in the signal injector 120 or in-linebetween the processing unit 102 and the signal injector 120. The signalis converted into an acoustic wave by TXMTR 110, which can be aloudspeaker or similar transducer. The acoustic wave first propagatesdown an interface tube 112, where it can be detected and/or recorded bya sensor, such as a pressure sensor 108. Sensor 108 may be a transducer,a microphone or any of a variety of other devices that can detect asignal. The acoustic wave can be a pulse of an acoustic wave for examplethen travels down a tube 114—the target tube that is being examined. Inthe illustrated embodiment the target tube 114 is shown to be a heatexchanger tube as an example. Any change in cross section of the targettube 114 will cause a reflection that will propagate back up the tube114 and the interface tube 112, to be recorded by the pressure sensor108, amplified by a pre-amp 104 and stored in the computer 102. Therecorded reflections are analyzed in the computer 102 in order toidentify the types and or severity of the faults that caused or resultedin creating the reflections. As non-limiting examples, the faults may beblockages (full or partial), pitting, erosion, cracks, kinks, bulges andholes. It will be appreciated that in some embodiments, multipleinterface tubes can be utilized with each having a pressure sensor 108but being fed by the same transmitter. In such embodiments, multipletubes can be tested at the same time or in consecutive fashion.

In addition to the measuring process as disclosed above, processing unit102 can be configured to store measuring results from previous cleaningprocess including the performance of the bundle of tubes before andafter each cleaning cycles. This data can be stored in a memory element(such as within an associated database structure in the memory element)and such memory element can be external or in internal permanent memoryof the processing unit 102 itself. The stored data can be used forstatistical analysis for determining a current situation of each tube inthe buddle and the situation of the bundle as a whole.

The stored information can include parameters to identify the interiorstate of the tube, such as but not limited to: the cleaning date, theperformance of the bundle before a cleaning cycle, the results ofmeasuring the dirt in the bundle before cleaning, dirt values aftercleaning and the bundle's performance after cleaning. The performance ofa bundle can be defined for example by: the temperature difference ofthe liquid between the temperature in the ingress of the bundle and thetemperature at the egress of the bundle, the pressure differentialsbetween the pressure of the ingress and egress of the bundle; the flowspeed; etc. The dirt values can be referred as the parameters regardingthe current cleanliness level of the bundle. Exemplary dirt values canbe represented in one or more ways, for example: a rate value orroughness value, the number of blockages above a certain amplitude per ameter of a tube or the distribution of peaks in the signal (number andheight) per tube or per a group of tubes; an amplitude value: an averageamplitude of a blockage in a pipe, in the bundle; the maximum amplitudeof the worse blockage in a tube, which is above a certain level, etc.

Processing unit 102 can be further configured to process the stored dataand based on current measurements and the stored data, including thetime differences between the cleaning processes of the stored data candetermine whether cleaning process is needed or when a next cleaningprocess needs to be performed, or whether a cleaning can help or if atube should be replaced or plugged. More information of the operating ofprocessing unit 102 is disclosed below in conjunction with FIG. 5 andFIG. 6.

It will be appreciated that the measuring and evaluating system canadvantageously be used in tubes that are not necessarily linear oruniform. For instance, the tubes under test may have bends and may havevarying inner diameters. In some embodiments, the processing unit canfilter out reflections from known obstructions, such as bends ordiameter changes and so to only provide information on blockages, cracksor other anomalies. In other embodiments, the processing unit can employsignal processing capabilities to identify and differentiate betweenreflections from tube bends and/or diameter changes from otheranomalies. In yet other embodiments, reflection signatures can be takenand recorded for new tubes that are known to be free from anomalies andthese stored signal signatures can then be used to filter out subsequentsignal recordings of tubes under test. It will also be appreciated thatdifferent types, patterns, frequencies, etc. of signals can be used todetect different anomalies. For instance, some deposit materials may bemore reflective at certain frequencies than at others and thus, usingspecific signal frequencies to detect for particular deposits mayimprove the accuracy of the detection.

FIG. 2 is a waveform timing diagram that illustrates typical reflectionsfrom a local blockage and a local degradation in a target tube. Thereflections illustrated in FIG. 2 are non-limiting examples of thereflections from different faults in an exemplary target pipe. Supposingthe impinging acoustic pulse 201 to be a sharp positive pulse asdepicted in FIG. 2, the reflection from a local blockage will appear asa positive pulse (reflected from the leading edge of the blockage)followed by a negative pulse (reflected from the terminating edge of theblockage) as depicted as element 202. A reflection from wall loss suchas pitting or erosion will be a negative pulse (reflected from theleading edge of the wall loss) followed by a positive one (reflectedfrom the terminating edge of the wall loss) as depicted in element 203.More information on an exemplary NDT application and the faults isdescribed in U.S. patent application Ser. No. 11/996,503, the content ofwhich incorporated herein by reference.

After observing a plurality of tubes before and after cleaning, it hasbeen discovered that there are differences between the reflection comingfrom clean tubes and unclean tubes. More specifically, it was determinedthat tubes that have been cleaned prior to an NDT inspection will haveisolated identifiable faults such as those presented in FIG. 2. Dirtytubes, on the other hand, have densely spaced fouling and deposits whichare in effect, multiple closely spaced blockages. Upon presentment of animpinging pulse in such an environment, this results in multiple closelyspaced peaks in the signal recorded by pressure sensor 108 (FIG. 1).Removal of the deposits from the tube during the cleaning process willresult in the reflected signals having lower peaks, as the depositsbecome smaller. The differences are demonstrated in FIG. 3 and FIG. 4.

FIG. 3 is a signal diagram illustrating overlaid traces of measurementsfrom several exemplary dirty tubes. Upon examination of FIG. 3, it isclear that there are prominent peaks (such as peak 301, 302, 303 and304) indicating several large blockages, and an overall noisiness shownas existing between levels 310 and 312 corresponding to rough internalsurface of the tubes, due to deposits.

FIG. 4 is a signal diagram illustrating overlaid traces of signalscorresponding to internal surface of the target tubes after cleaning.Measurements taken from the same group of target tubes after cleaningare illustrated in FIG. 4. As is clearly shown in FIG. 4, the signalsreside between lines 410 and 412 and are much more uniform, and smootherthus corresponding with a smoother internal surface of the target tubes.

FIG. 5 is a flow diagram illustrating relevant acts of an exemplarymethod for analyzing and evaluating the effectiveness of a cleaningprocess. Within an environment of a heat exchanger, the exemplary method500 can take measurements over a large number of tubes and then performa statistical analysis of these measurements in order to present theuser with an overall picture of the condition of the heat exchangerbeing examined. Further, the information is stored in a database orpermanent memory and be used as statistical data for future cleaningprocesses. In some embodiments the bundle performance before and aftercleaning can be taken too and be used for analyzing the dirt situationin the bundle. This overall picture can provide the user with metricsregarding the likelihood of the occurrence of a breakdown on a per tubebasis, groups of tubes, or the entire heat exchanger. Non-limitingexamples of some of the statistics that can be determined include, butare not limited to the following list: average number of blockages, in atube and/or in the bundle, above a certain threshold, worse blockage pertube, measures of roughness compiled from the distribution of peaks inthe signal (number and height) per tube or per a group of tubes, anaverage number of cleaning that is required in order to reach a requiredlevel of cleanness of tubes in a certain condition, etc. Generally, thecauses of dirt in the tubes may vary according to many factorsincluding, but not necessarily limited to, the types of tubes and theenvironments in which the tubes are operating. The contamination can becaused by sludge, scaling, marine organisms, corrosion etc. The numberof cleaning cycles required to reduce deposits or accumulations in atube to acceptable levels depends strongly on the type of the deposits,and therefore also varies. Thus, a cumulative knowledge base built intothe system and incorporating the results from all or a large number ofthe previous sessions can be used as the accumulated information (i.e.,tube type, operating environment, number of actual cleaning cycles) togive an estimate of the number of cleaning cycles required to achieve arequested or target degree of cleanliness.

The exemplary APR system that is illustrated in FIG. 1 can be used inconjunction with the acts of method 500 to measure and store in adatabase a random sample of tubes or all the tubes in a bundle of tubesprior to cleaning 510. In some exemplary embodiments act 510 furtherincludes measuring and storing the bundle performance before thecleaning. The system conducts an analysis of the cleanliness (the levelof dirt in the bundle of tubes) of the measured sample of tubes comparesit to information stored in the database and then reports on the levelof cleanliness 520. In the exemplary embodiments in which theperformance of the bundle is measured and stored, those parameters arealso processed in addition to the cleanliness level. The level ofcleanliness (the dirt values) can be expressed by the average number ofblockages above a certain threshold in a tube from the plurality oftubes, worse blockage per tube, measures of roughness compiled from thedistribution of peaks in the signal (number and height) per tube or pera group of tubes, etc. The performance values can be expressed by thetemperature difference of the liquid between the temperature in theingress of the bundle and the temperature at the egress of the bundle,the pressure falls between the pressure of the ingress and egress of thebundle; the flow speed; etc.

Based on past similar cases available to the system or stored within itsknowledge base, the system estimates the number of cleaning cyclesrequired to bring the tubes to an accepted level of cleanliness 530. Thesystem can then enter a loop that includes the performance of a cleaningstage 540 followed by the process of measuring all or a random sample ofthe tubes 550 and then again, analyzing the cleanliness of the tubes 560based on the most recent cleaning stage. In some embodiments act 550 mayfurther include measuring and storing the bundle performance after thecleaning.

In some embodiments, the knowledge base can be stored in database andafter each cleaning stage or session, the database can be updated withthe new results. The database can be organized and structured in avariety of ways, for instance, the entries may be divided according tothe type of tubes, the application of the bundle, etc. After eachcleaning cycle, the system determines if 570 the cleanliness level ofthe tubes has met the target requirements. In some embodiments thedecision can be based also on the performance measurement of the bundleof tubes, yet in other embodiment, the decision can be based on both:the level of dirt (or cleanliness level) and the performance o thebundle. If not, this process is repeated by returning to the act ofperforming a cleaning stage 540. In some embodiments, if after severalcleaning process the bundle performance and/or the level of dirt are notimproved then method 500 may recommend to replace one or more tubes orthe entire bundle.

However, if 570 the cleanliness level of the tubes has met the targetrequirement, the process stores the date and the number of cleaningcycles in the database to be used for future cleaning processes andgenerates and produces a detailed report. In some embodiments, thereport shows quantitative measures described above for the initial,interim and final conditions of the tubes.

The system can also be used to determine the rate of debrisaccumulation. For instance, if measurements are taken and stored on aperiodic basis following a cleaning, then data can be accumulatedregarding how long it takes, following a cleaning cycle, for the debristo accumulate to a threshold level. After accumulating this data over aperiod of time, the system can then accurately estimate when the nextcleaning cycle is due.

Some exemplary embodiments of an evaluation system can be configured tocollect information regarding the overall geometry or structure of thetubing in the bundle. In such embodiments, reflections of signals causedby bends, compressions, joints, etc., are expected to the system and canbe filtered out as not being caused by accumulations within the tubes.

The various embodiment of the measuring device can be implemented as astand-alone apparatus, or integrated with cleaning equipment or acleaning system. Further, the measuring device could be implemented as atool for testing one tube at a time, or together with a roboticmanipulator as a system for automatically testing a large number oftubes.

Some exemplary embodiments may include a centralized updating center.Such a center can include a server that can be loaded from time to timewith the results generated by a plurality of users regarding the historyof their cleaning sessions. Based on the enlarged collected data, theserver can perform statistical analyses in order to determine therequired number of cleaning cycles needed to clean a bundle of tubes.The updated formulations can be loaded back to the users' equipment.

FIG. 6 is a functional block diagram of the components of an exemplaryembodiment of the measuring system, as well as other embodimentsthereof. It will be appreciated that not all of the componentsillustrated in FIG. 6 are required in all embodiments of the measuringdevice but, each of the components are presented and described inconjunction with FIG. 6 to provide a complete and overall understandingof the components. Further, many specific elements are not presented inFIG. 6 but rather functions and/or functional interfaces are used in ageneric fashion to indicate that various embodiments may use a varietyof specific components or elements. The measuring system can include ageneral computing platform 600 illustrated as including a processor 602and a memory device 604 that may be integrated with each other (such asa microcontroller) or, communicatively connected over a bus or similarinterface 606. The processor 602 can be a variety of processor typesincluding microprocessors, micro-controllers, programmable arrays,custom IC's etc. and may also include single or multiple processors withor without accelerators or the like. The memory element of 604 mayinclude a variety of structures, including but not limited to RAM, ROM,magnetic media, optical media, bubble memory, FLASH memory, EPROM,EEPROM, internal or external-associated databases, etc. The processor604, or other components may also provide components such as a real-timeclock, analog to digital converters, digital to analog converters, etc.The processor 602 also interfaces to a variety of elements including acontrol or device interface 612, a display adapter 608, audio/signaladapter 610 and network/device interface 614. The control or deviceinterface 612 provides an interface to external controls or devices,such as sensor, actuators, transducers or the like. The device interface612 may also interface to a variety of devices (not shown) such as akeyboard, a mouse, a pin pad, and audio activate device, a PS3 or othergame controller, as well as a variety of the many other available inputand output devices or, another computer or processing device. The deviceinterface may also include or incorporate devices such as sensors,controllers, converters, etc. For instance, the amplifier 106, thetransmitter 110, the preamp 104 and the sensor 108 illustrated in FIG. 1could all be included in the device interface 612 either as internal orintegrated components or, the device interface 612 may interface to thedevices as external components. Alternatively the processing unit 102illustrated in FIG. 1 could interface to the measuring elements as astand-alone third party system through control lines, a wired network ora wireless network. The display adapter 608 can be used to drive avariety of alert elements and/or display devices, such as displaydevices including an LED display, LCD display, one or more LEDs or otherdisplay devices 616. The audio/signal adapter 610 interfaces to anddrives another alert element 618, such as a speaker or speaker system,buzzer, bell, etc. In the various embodiments of the measuring device,the audio/signal adapter could be used to generate the acoustic wavefrom speaker element 618 and detect the received signals at microphone619. The amplifiers, digital-to-analog and analog-to-digital convertersmay be included in the processor 602, the audio/signal adapter 610 orother components within the computing platform 600 or external there to.The network/device interface 614 can also be used to interface thecomputing platform 600 to other devices through a network 620. Thenetwork may be a local network, a wide area network, wireless network, aglobal network such as the Internet, or any of a variety of otherconfigurations including hybrids, etc. The network/device interface 614may be a wired interface or a wireless interface. The computing platform600 is shown as interfacing to a server 622 and a third party system 624through the network 620. A battery or power source 628 provides powerfor the computing platform 140.

In the description and claims of the present application, each of theverbs, “comprise” “include” and “have”, and conjugates thereof, are usedto indicate that the object or objects of the verb are not necessarily acomplete listing of members, components, elements, or parts of thesubject or subjects of the verb.

Various aspects and embodiments of the invention have been described areprovided by way of example and are not intended to limit the scope ofthe invention. The described embodiments comprise different features,not all of which are required in all embodiments. Some embodimentsutilize only some of the features or possible combinations of thefeatures. Variations of embodiments described and embodiments comprisingdifferent combinations of features noted in the described embodimentswill occur to persons of the art.

It will be appreciated by persons skilled in the art that the presentinvention is not limited by what has been particularly shown anddescribed herein above. Rather the scope of the invention is defined bythe claims that follow.

1.-20. (canceled)
 21. A system for evaluating the interior state of oneor more associated tubes, comprising: a processing unit; a memoryelement communicatively coupled to the processing unit; a signalinjector interfacing with the processing unit; a signal detectorinterfacing with the processing unit; and an interface element that iscoupled to the signal injector and the signal detector and is configuredto interface with one tube, at a time, of the bundle of tubes undertest; wherein the processing unit is configured to at least partiallycontrol the signal injector to cause the injection of a signal into theinterior of a current-measured tube of the associated tubes through theinterface element; wherein the signal detector is configured to detect asignal reflected back out of the current-measured tube through theinterface element and provide information regarding the reflected signalto the processing unit; and wherein the processing unit is furtherconfigured to process the information regarding the reflected signalreceived from each one of a plurality of measured tubes of theassociated tubes, to deduce one or more parameters regarding the currentinterior state of the associated tubes and to store the deduced one ormore parameters in the memory element.
 22. The system of claim 21,wherein said interface element comprises multiple interface tubes beingcoupled to the same signal injector and the same signal detector andbeing configured to interface with multiple tubes under test, at thesame time or in a consecutive fashion, wherein said processing unit isconfigured to at least partially control the signal injector to causethe injection of a signal into the interior of the multiple tubesthrough the interface tubes; wherein the signal detector is configuredto detect a signal reflected back out of the multiple tubes through theinterface tubes and provide information regarding the reflected signalfrom each one of the multiple tubes to the processing unit; and whereinthe processing unit is further configured to process the informationregarding the reflected signal received from each one of the multipletubes under test, to deduce one or more parameters regarding the currentinterior state of the multiple tubes and to store the deduced one ormore parameters in the memory element to thereby evaluate the interiorstate of multiple tubes.
 23. The system of claim 22, wherein the one ormore parameters regarding the current interior state are statisticalinformation selected from a group consisting of an average roughnessvalue, the average size of a blockage, and the size of the biggestblockage in the multiple tubes.
 24. The system of claim 22, wherein theprocessing unit is further configured to collect one or more parametersregarding the current performance of the multiple tubes and store it inthe memory element.
 25. The system of claim 23, wherein the one or moreparameters regarding the current performance are selected from a groupconsisting of temperature difference between the ingress and the egressof the multiple tubes, the pressure difference over the multiple tubes;and the flow speed.
 26. The system of claim 23, wherein the processingunit is further configured to compare at least one of the collected oneor more parameters regarding the performance of the multiple tubes andthe deduced one or more parameters regarding the current interior stateof the multiple tubes to previously stored information in order todetermine whether a remedial process is necessary.
 27. The system ofclaim 25, wherein the processing unit is further configured to determinethe number of remedial cycles required to bring said multiple tube to adesired interior state.
 28. The system of claim 22, wherein the signalinjector includes a transmitter that is configured to transmit anacoustic wave toward each interface tube.
 29. The system of claim 22,wherein the one or more parameters regarding the current interior stateof the multiple tubes comprises an average number of blockages in a tubeabove a certain threshold.
 30. The system of claim 22, wherein themultiple tubes are part of a heat exchanger.
 31. The system of claim 22,wherein each interface tube comprises a pressure sensor.
 32. The systemof claim 21, wherein said processing unit is configured and operable tofilter out reflections signatures indicative of known obstructionsincluding bends and diameter changes to thereby provide information onblockages, cracks or other anomalies.
 33. The system of claim 21,wherein said processing unit is configured and operable to performsignal processing to identify and differentiate between reflections fromtube bends and/or diameter changes from other anomalies.
 34. The systemof claim 21, wherein said processing unit is configured and operable toidentify different types, patterns or frequencies of signals to detectdifferent anomalies.
 35. The system of claim 21, wherein said processingunit is configured and operable to detect specific signal frequenciesbeing indicative of at least one particular deposit.
 36. A method forevaluating the interior state of a plurality of associated tubes, themethod comprising the action of identifying the interior state ofselected tubes from the associated tubes by conducting the acts of:interfacing an interface element of a measuring device to one targettube selected from a plurality of tubes to be tested; injecting a signalfrom the measuring device into the selected target tube such that thesignal propagates through the interface element and into the selectedtarget tube; detecting at the measuring device, signal reflectionsexiting from the selected target tube via the interface element;repeating the previous acts per each tube from the selected tubes of theassociated of tubes; and processing the signal reflections from eachtube of the selected tubes, to deduce one or more parameters regardingthe current interior state of the associated tubes and to store thededuced one or more parameters into a memory element.
 37. The method forclaim 36, wherein, the method comprising: interfacing multiple interfacetubes of a measuring device to multiple tubes to be tested; injecting asignal from the measuring device into the multiple tubes such that thesignal propagates through the interface tubes and into the multipletubes; detecting at the measuring device, signal reflections exitingfrom each tube of the multiple tubes via the interface tubes; repeatingthe previous acts per each tube from the multiple tubes; and evaluatingthe interior state of the multiple tubes.
 38. The method of claim 36,wherein said processing of the signal reflections comprises using knownsignal reflections from clean tubes.
 39. The method of claim 36, whereinsaid processing of the signal reflections comprises filter outreflections signatures indicative of known obstructions including bendsand diameter changes to thereby provide information on blockages, cracksor other anomalies.
 40. The method of claim 36, wherein said processingof the signal reflections comprises identifying and differentiatingbetween reflections from tube bends and/or diameter changes from otheranomalies.
 41. The method of claim 36, wherein said processing of thesignal reflections comprises identifying different types, patterns orfrequencies of signals to detect different anomalies.
 42. The method ofclaim 36, wherein said processing of the signal reflections comprisesdetecting specific signal frequencies being indicative of at least oneparticular deposit.